Process for converting petroleum oil



Sept 39,* 1933. c. P. DUBBS PROCESS FOR CONVERTING PETROLEUM OIL ginal Filed Oct. 21, 1922 (W75 mi @Jh ein for fa/ban TDabas,

Patented sept. 19, 1933 UNITED STATES 1,92 ,156 PROCESS FOB CONXRTWG Carbon P. Dubbs, Wllmette, Ill., signor to The Universal Oil Products Company, Chicago, lll., a corporation of South Dakota Application October 2l, 1922, Serial No. 595,946

Renewed July 17, 1930 3 Claims. (Cl. 196-58) This invention relates to improvements ina process for converting petroleum oil, and refers more particularly to a process in which relatively high boiling point oils are reduced to oils of a low boiling point having the characteristics of gasoline and the like.

Among the salient objects of the invention, are to provide a process in which after raising the oil to a conversion temperature, and collecting it in a substantial body under pressure in a vaporizing zone, the vaporous portion of the oil is subjected to successive dephlegmation and a final condensing action, while a substantial portion of the liquid is vaporized at atmospheric conditions with or without treatment by superheated steam; to provide a process in which the oil is separately treated for extracting the light products by first subjecting it to vaporization under pressure conditions and subsequently to atmospheric distillation.

The single gure is a diagrammatic side elevational view of the apparatus with parts in section.

Referring to the drawings, the raw oil to be treated is introduced through the line 1 and is charged by means of the pump 2 into the preheater 3 which consists of tubes 4 communicating with upper and lower headers 5 and 6. The oil is charged to the preheater to circulate about the tubes through which the vapors pass.

In this manner, the temperature of the oil is raised prior to its introduction to the system. From the preheater the oil passes through the line 'l and is circulated through a closed coil 8 which is positioned in the insulated dephlegmator 9. In its circulation through this coil, the oil serves as a dephlegmating medium ior the vapors which rise through the column 9. During dephlegmation, the temperature of the oil in the coil is further increased. The discharge end of the coil 8 is connected with a line 10 which directs the heated oil to a spray positioned in the top of the second dephlegmator 11. The raw oil being introduced into the top of this column cornes in intimate contact with the vapors rising therethrough, thus a further separation or dephlegmation of the vapors is eiected.

The oil with what condensate it may collect in the column 11 passes downwardly over the perforated pans 12, and collects in the lower leg 13 of the dephlegmator 11. This oil is drawn oif through the line 14 in which is interposed a valve 15 and is directed to the leg 16 of the dephlegmator 9. Here the liquid oil constituents combine with the condensate separated out in the initial column, and are drawn off through the line 17 controlled by the valve 18 and charged to the heating coil 19 positioned in the furnace 20. The oil, after passing through the furnace and being raised to a conversion temperature, is directed to the transfer line 21 controlled by valve 22, to an initial insulated vaporizing chamber 23 which is equipped with a vapor outlet pipe 24 controlledv by valve 25 communicating with the dephleg-V mator 9, and a residuum draw-off line 26 controlled by valve 2'1. At different heights on the chamber 23 are positioned lines 28 respectively cont-rolled by valves 29 which communicate with the common pipe 30 communicating with an adjoining insulated chamber 31 which likewise has a vapor draw-ofi line 32 controlled by valve 33. and a residuum draw-off line 34 controlled by valve 35. The vapor line 32 communicates with a condenser coil 36 which in turn is connected by a line 37 to receiving tank 38.

The vapors from the initial vaporizing zone as stated, pass off through` the line 24 and rise through the dephlegmator 9 where they are sub-J' jected to the dephlegmating action of the rawioil coil and contact with pressure distillate returned from the final receiving tank 43 hereinafter described. The uncondensed vapors pass ofi from the top of the dephlegmator through the line 39 and may be directed by manipulation of the valves 40 and 41 to pass either directly to the preheater 3 and thence to the condenser 42 and receiver 43, or by closing the valve 40 and opening the valve 41 they may be introduced into the bottom of the dephlegmator 11 and there subjected to further dephlegmation. As explained, the dephlegmation in the second column l1 is eiected by the introduction of the raw oil into its uppermost portion and the opposed ilow of the vapors and the downcoming raw oil over the series of perforated pans. if the vapors are caused to ow in this manner, that is through the successive dephlegmators, the still vaporized portion passes oi from the column 11 through the line 44 and may be directed to the preheater 3 and condensing coil 42 by opening the valve 45; or by closing the valve 45 and opening the valve 46 in the line 47 the vapors will pass into the condenser coil 48 and be collected as distillate in the receiver 49 which is connected thereto by a line 50 controlled by a valve 51. The receivers have pressure relief pipes 52 controlled by valves 53. These pipes are interconnected by a line 54 in which is interposed a valve 55, thus a common pressure may be maintained upon both receivers or diierential pressure as desired.

The distillate collected in the receiving tanks 43 and 49 may be drawn oi through the lines 56 and 57 and returned through line 58 and pump 59 to a pipe 60 communicating with secondary lines 61 and 62 which terminate in the spray pipes positioned in the top of the dephlegmators. Valves 63, 64 and 65 are interposed in the lines 60, 61 and 62 respectively.

Besides the heating coil 19, there is positioned in the furnace 20 a steam coil 66 which supplies steam through the line 67 to a perforated rose or pipe 68 positioned in the bottom of the Vaporizing chamber 3l. A. valve 69 is positioned in the line 67 to control the introduction ci steam thereto.

ln operation, the oil which is preferably a charging stock for cracking stills which may be gas oil, kerosene or similar distillates, fuel oil or other oils which are commercially feasible to be treated, is preheated by rirst being passed through the heat interchanger B, thence through the coil 8 from which it is introduced into the top or the dephlegmator il. After serving as a dephlegmating'medium therein, it is collected and drawn E through the lower ieg or the dephlegmator ll and is combined with the liquid oil constituents separated out in the adjoining dephlegmator or rectifying column 9 and passed through the line i7 to the heating coil 19 where it is raised to a conversion temperature under substantial pressure. ritem-- peratures from 600 to 900 F., with pressures ranging from 50 to 30o pounds per square inch are used. These temperature and pressure conditions vmay be varied according to the character oi the oil treated, and the type of distillate which it is desired to obtain.

The heated oil from the heating coil passes through the transfer line into the expansion vaporizing chamber 23, -where there is a substantial portion of the oil converted in the form of vapor and gases. These vapor constituents rise through the line 2d, and are subjected to a reuxing action in the initial dephlegmating column 9. v

The unvaporized portion may be drawn oil, or a level maintained in the chamber 23 by controlling the liquid draw-od line 26 by the valve 27. Furthermore, this liquid unvaporized in the initial chamber may be drawn oli .through the line 28 controlled by the valves 29 and introduced to the chamber 31. This chamber may be operated under substantial reduced pressure or atmospheric conditions. The introduction oi-the oil thereto will cause an immediate evolution of vapors due to the reduction in pressure, which will pass oli through the line 32 and be condensed and collected in the condensing apparatus 36 and receiver 38. To assist the distillation of the liquid oil constituents in the chamber 3l, there may be introduced thereto superheated steam which is passed through the coil 66 mounted in the furnace 20, thus an initial distillation under pressure is effected, and a subsequent steam distillation or distillation under reduced pressure or atmospheric conditions is carried on, the vapors from each vaporizing chamber being separately treated.

Returning now to the travel of the vapors evolved under the higher pressure distillation, after being subjected to an initial dephlegmation in the column 9, they may be passed over and immediately condensed and collected in the receiver 43, or by manipulation of the valves 40 and 4l they may be directed through a secondary refluxing column under the same or reduced pressure.

An alternate method of operation would be to direct part oi the vapors immediately to final condensation in the condenser 42 and a portion of the vapors through the secondary dephlegmator under the same or reduced pressure. The vapors subjected to secondary dephlegmation in the column ll may be separately collected in the receiver 49 by proper control of the valves l4:5 and 46.

The apparatus aords a number of variations which may be used at dierent times during the operation, so as to produce the most advantageous results and the best quality products,

negarse The temperature ln the dephlegmating stages may be more or less controlled not only by the circulation of the raw oil, but also by the rey cycling of the nal distillates from the receivers back and introducing them into the top of the dephlegmating stages. These distillation oils are of a more refractory character than the raw oil.

" densatlon are interconnected and'valves are supplied in these connections for maintaining the same or dierential pressures therein, thusa further variation may be had in the operation oi the apparatus.

il claim as my invention:

l. A process ior .converting petroleum oil consisting in heating the oil to a conversion temperature in a heating zone, vaporizing the heated oil While maintaining it in a substantial body in a vaporizing zone,I passingthe evolved vapors through independent zones of successive dephlegmation and condensing the still vaporized oil constituents passing over from the nal dephlegmating zone, utilizing the charging stock as a dephlegmating medium in a secondary zone of dephlegmation and portions oi the condensed distillate in the primary zone, said portions ci the condensed distillate being in direct contact with the vapors in the primary zone, and maintaining a regulated pressure upon the system during treatment.

2. A process for converting petroleum oil consisting in heating the oil to a conversion temperature in a heating zone, vaporzing the heated oil while maintaining it in a substantial body in a vaporizing zone, passing the evolved vapors through zones of successive dephlegmation and condensing the still vaporized oil constituents passing over from the nal dephlegmating zone, utilizing the charging stock as a dephlegmating medium in a secondary zone of dephlegmation and portions of the condensed distillate in the primary zone, said portions of the condensed distillate being in direct contact with the vapors in the primary zone, condensing and collecting separately, portions of the uncondensed vapors from each of thev dephlegmating zones, and maintaining a regulated pressure on the system.

3. A process for converting petroleum oil consisting in heating the oil to a conversion temperature in a heating zone, vaporizing the heated oil while maintaining it -in a substantial body in a vaporizing zone, passing the evolved vapors through successive zones of dephlegmation, and condensing the still vaporized oil constituents passing over from the nal dephlegmating zone, utilizing the charging stock as a dephlegmating medium in a secondary zone of dephlegmation, and the condensed distillate in the primary zone, and maintaining a regulated pressure upon the heating, vaporizing, dephlegmating and condensing zones, passing the unvaporized oil from the initial zone of vaporization to a secondary vaporizing zone, and there promoting further distillation under reduced pressure and in the presence of superheated steam;

, 0N P. DUBBS. 

